It doesn't allow for possibly appearing too high on the screen and getting the top cut off. Ideally, it'd be set up where when this happens the arrow moves to the top of the hint and the hint appears below the series point.

You can't tweak the move animation. Could put the config for it as a property of the interaction like how the hint config is.

When you toggle a series to hide it, any showing hint won't be hidden. Right now there is no hide/show event for series, so there's no good way to tap into this process. I've entered a feature request. Hopefully this will get added before release.